We have term called as "Gulu" which means going very extreme which is absolutely not Islamic. Islam teaches a simple, moderate and consistent life. Even if you are on a battle field you are not suppose to eat each other..oh such a cannibalism was never seen in Islamic History by Muslims..of course Non Muslim Arabs have done such cruel acts like making a necklace of other's body parts and intend to drink wine on enemies skull.. pork & wine becomes halal in some survival situations but not human meat...never